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22 Jan 1996

Volume 68, Issue 4, pp. 435-574

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Femtosecond intersubband relaxation and population inversion in stepped quantum well

C. Y. Sung, T. B. Norris, A. Afzali‐Kushaa, and G. I. Haddad

Appl. Phys. Lett. 68, 435 (1996); http://dx.doi.org/10.1063/1.116404 (3 pages) | Cited 14 times

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We have investigated intersubband relaxation rates in a stepped quantum well at room temperature using differential transmission spectroscopy with subpicosecond time resolution. The dynamics of the subband populations are derived from the experimentally observed reduction of oscillator strength of the corresponding exciton transitions. In the stepped quantum well the relaxation through longitudinal optical‐phonon emission from n=3 to 1 (25 ps) is slower than that from 2 to 1 (220 fs), due to the reduced wave function overlap and larger wave vector required for intersubband scattering. When the n=3 state is pumped, a population inversion between n3 and n2 (which are separated by 7 THz) is observed. © 1996 American Institute of Physics.
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78.47.-p Spectroscopy of solid state dynamics
78.66.Fd III-V semiconductors

1.5 μm photoluminescence of Er3+ in YF3, LuF3, and LaF3 thin films

Ch. Buchal, Th. Siegrist, D. C. Jacobson, and J. M. Poate

Appl. Phys. Lett. 68, 438 (1996); http://dx.doi.org/10.1063/1.116405 (3 pages) | Cited 11 times

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We have studied the photoluminescence at 1.5 μm of the 4I13/2→4I15/2 transition of the Er3+ ion, incorporated as ErF3 into polycrystalline YF3, LuF3, and LaF3 films, deposited onto SiO2 or Si wafers. We conclude that LaF3 is an exceptionally suitable host for Er3+, since it permits high Er3+ concentrations, long lifetimes of the excited level, and a strong Stark splitting. This results in a spectral shape suitable for broadband optical amplifiers with a usable optical bandwidth exceeding 8000 GHz (Δλ≂60 nm). © 1996 American Institute of Physics.
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71.55.Ht Other nonmetals
78.30.Hv Other nonmetallic inorganics
78.55.Hx Other solid inorganic materials

Refractive indices of zincblende structure β‐GaN(001) in the subband‐gap region (0.7–3.3 eV)

M. A. Vidal, G. Ramírez‐Flores, H. Navarro‐Contreras, A. Lastras‐Martínez, R. C. Powell, and J. E. Greene

Appl. Phys. Lett. 68, 441 (1996); http://dx.doi.org/10.1063/1.116406 (3 pages) | Cited 13 times

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Refractive indices n and absorption coefficients α of epitaxial metastable zincblende structure β‐GaN(001) were determined over the subband‐gap energy range between 0.8–3.1 eV from an analysis of optical transmission spectra. n was found to vary from 2.25 to 0.8 eV (1.55 μm) to 2.50 at 3.1 eV (0.4 μm) with an energy E (eV) dependence that is well described by a Sellmeir‐type dispersion relationship, n2(E)=1+148/(38.3−E2). The refractive indices of β‐GaN are 3%–4% smaller than previously reported values for hexagonal α‐GaN. © 1996 American Institute of Physics.
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78.20.Ci Optical constants (including refractive index, complex dielectric constant, absorption, reflection and transmission coefficients, emissivity)
78.66.Fd III-V semiconductors

Localization‐induced blueshift in quantum wires: Direct evidence from magnetophotoluminescence measurements

G. Lehr, V. Härle, F. Scholz, and H. Schweizer

Appl. Phys. Lett. 68, 444 (1996); http://dx.doi.org/10.1063/1.116407 (3 pages)

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For In0.53Ga0.47As/InP quantum wires fabricated from quantum well material by dry etching and epitaxial regrowth, a blueshift with decreasing wire width is found, where the blueshift is larger than expected by lateral quantization. In magnetophotoluminescence, the quantum well clearly displays a feature that is due to carrier transport between growth islands of different well widths. This feature cannot be observed for small wire structures, which means that the carrier transport is suppressed in these structures. Hence, magnetophotoluminescence measurements give new direct evidence for the fact that the excitons are more and more localized in states of higher energy as the wire width is decreased, which explains the blueshift in the optical spectra. © 1996 American Institute of Physics.
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78.55.Cr III-V semiconductors
78.66.Fd III-V semiconductors

Experimental study of dispersive effects in fiber ring lasers

D. Prasad, R. Fortenberry, and R. Zanoni

Appl. Phys. Lett. 68, 447 (1996); http://dx.doi.org/10.1063/1.116408 (2 pages) | Cited 1 time

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The effects of dispersion on the pulsewidth of a mode‐locked fiber ring laser are examined. We have identified two different modes of operation, one where the pulsewidth is determined by the path‐integrated (global) dispersion of the cavity and another novel mode where pulsewidth is not limited by the global dispersion. Experimental results show that for some configurations, the local dispersion of the cavity plays an important role in determining the pulsewidth of the laser. © 1996 American Institute of Physics.
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42.55.Wd Fiber lasers
42.60.Fc Modulation, tuning, and mode locking

Spectral effects in short pulse pump‐probe measurements

J. Mørk, A. Mecozzi, and C. Hultgren

Appl. Phys. Lett. 68, 449 (1996); http://dx.doi.org/10.1063/1.116409 (3 pages) | Cited 9 times

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Spectral effects arising from linear gain dispersion are shown to strongly influence the ultrafast gain dynamics measured in active semiconductor waveguides using the pump‐and‐probe technique. Measurements on a AlGaAs amplifier under varying amounts of gain dispersion are in good agreement with a simple analytical theory derived from semiclassical density matrix equations. © 1996 American Institute of Physics.
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42.60.Da Resonators, cavities, amplifiers, arrays, and rings
78.47.-p Spectroscopy of solid state dynamics
78.66.Fd III-V semiconductors

High average power, high‐repetition rate femtosecond pulse generation in the 1–5 μm region using an optical parametric oscillator

D. E. Spence, S. Wielandy, C. L. Tang, C. Bosshard, and P. Günter

Appl. Phys. Lett. 68, 452 (1996); http://dx.doi.org/10.1063/1.116410 (3 pages) | Cited 10 times

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We describe the operation of a high average power, high‐repetition rate, femtosecond optical parametric oscillator in the important 3–5 μm spectral region. The Ti:sapphire pumped optical parametric oscillator was based on the nonlinear material potassium niobate. The idler wavelength was continuously tunable over the 2.3–5.2 μm region and average powers as high as 170 mW were measured. At 5.2 μm, average powers of more than 20 mW were recorded. Idler pulse durations were determined using cross‐correlation techniques and pulses as short as 60 fs were measured in the midinfrared. © 1996 American Institute of Physics.
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42.65.Yj Optical parametric oscillators and amplifiers

Nonlinear optical properties of photoresists for projection lithography

Anthony S. Kewitsch and Amnon Yariv

Appl. Phys. Lett. 68, 455 (1996); http://dx.doi.org/10.1063/1.116411 (3 pages) | Cited 25 times

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Optical beams are self‐focused and self‐trapped upon initiating crosslinking in photoresists. This nonlinear optical phenomenon is apparent only for low average optical intensities and produces index of refraction changes as large as 0.04. We propose using the self‐focusing and self‐trapping phenomenon in projection photolithography to enhance the resolution and depth of focus. © 1996 American Institute of Physics.
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42.65.Jx Beam trapping, self-focusing and defocusing; self-phase modulation
85.40.Hp Lithography, masks and pattern transfer

Raman spectra of MoO3 implanted with protons

T. Hirata, K. Ishioka, and M. Kitajima

Appl. Phys. Lett. 68, 458 (1996); http://dx.doi.org/10.1063/1.116412 (3 pages) | Cited 8 times

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The Raman spectra of MoO3 implanted with 1, 2, and 4×1016 H+/cm2 have been recorded at room temperature. It was found that most of the Raman modes of Ag and Bg symmetry, which are observed between 100 and 1100 cm−1, decrease in intensity by the electronic screening of phonons as a result of the electron transfer from hydrogen to Mo. In addition, both Raman modes of Ag symmetry at 998 and 811 cm−1 for MoO3 noticeably stiffened at 4×1016 H+/cm2, while the orthorhombic structure of MoO3 remains unchanged exhibiting no significant change in lattice parameters except for any possible distortion of the MoO6 octahedron. The present results are compared with previous studies, in reference to structural information of the hydrogen molybdenum bronzes as well as MoO3. © 1996 American Institute of Physics.
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61.72.up Other materials
78.30.-j Infrared and Raman spectra

Scanning microdeformation microscopy in reflection mode

P. Vairac and B. Cretin

Appl. Phys. Lett. 68, 461 (1996); http://dx.doi.org/10.1063/1.116413 (3 pages) | Cited 20 times

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A scanning microdeformation microscope based on a vibrating tip with piezoelectric detection in a transmission operating mode is upgraded to operate in reflection mode. Images which reveal subsurface inhomogeneities in silicon and metallic samples are presented. As in the first configuration the lateral resolution and the apparent penetration depth is related to the tip diameter. © 1996 American Institute of Physics.
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07.79.-v Scanning probe microscopes and components
68.37.Ef Scanning tunneling microscopy (including chemistry induced with STM)
68.37.Ps Atomic force microscopy (AFM)
68.37.Rt Magnetic force microscopy (MFM)
68.37.Uv Near-field scanning microscopy and spectroscopy

Extraction of superthermal electrons in a high current, low emittance, steady state electron gun with a plasma cathode

Ady Hershcovitch

Appl. Phys. Lett. 68, 464 (1996); http://dx.doi.org/10.1063/1.116414 (3 pages) | Cited 17 times

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Major limitations of plasma cathodes have been overcome in an electron gun based on extraction of superthermal electrons from a discharge characterized by a large component of high energy electrons with a low thermal spread. A grid is employed to select these electrons for extraction while retaining the bulk electrons in the discharge. Steady state extraction of electron beams corresponding to over 60% of the total arc discharge current has been observed. This extracted electron current far exceeds the thermal electron flux. A perveance of over 280 microperv was reached with the extraction of 9 A at 1 keV from a 6 mm aperture. © 1996 American Institute of Physics.
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07.77.Ka Charged-particle beam sources and detectors
29.25.Bx Electron sources
52.75.-d Plasma devices

Feedback positioning cantilever using lead zirconate titanate thin film for force microscopy observation of micropattern

Toru Fujii and Shunji Watanabe

Appl. Phys. Lett. 68, 467 (1996); http://dx.doi.org/10.1063/1.116415 (2 pages) | Cited 18 times

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An atomic force microscope cantilever with PZT thin film with pyramidal stylus was used for actuation of feedback motion. The maximum stroke of the cantilever was more than 1 μm within a frequency range from direct current up to natural resonant frequency, e.g., 28.48 kHz. An image of a pit of a compact disk with a depth of 100 nm was successfully obtained using only cantilever actuation in a vertical direction. © 1996 American Institute of Physics.
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68.37.Ef Scanning tunneling microscopy (including chemistry induced with STM)
68.37.Ps Atomic force microscopy (AFM)
68.37.Rt Magnetic force microscopy (MFM)
68.37.Uv Near-field scanning microscopy and spectroscopy
68.35.B- Structure of clean surfaces (and surface reconstruction)

Assessment of nondiamond carbon levels present in chemical vapor deposited diamond by analysis of the plasmon loss features of x‐ray photoelectron spectra

S. Haq, D. L. Tunnicliffe, S. Sails, and J. A. Savage

Appl. Phys. Lett. 68, 469 (1996); http://dx.doi.org/10.1063/1.116416 (3 pages) | Cited 8 times

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The plasmon loss region of x‐ray photoelectron spectra has been analyzed for chemically vapor deposition diamond in order to assess the nondiamond carbon (NDC) levels present. A semiquantitative method for expressing the quality of the diamond, based upon the ratio of the diamond bulk plasmon to the main carbon 1s line is presented and a figure of merit defined. A comparison with Raman spectroscopy shows that this technique compares well in terms of range and sensitivity to NDC levels. © 1996 American Institute of Physics.
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68.55.Nq Composition and phase identification
79.60.Bm Clean metal, semiconductor, and insulator surfaces
81.15.Gh Chemical vapor deposition (including plasma-enhanced CVD, MOCVD, ALD, etc.)

Control of epitaxial growth of pulsed laser deposited LiNbO3 films and their electro‐optic effects

See‐Hyung Lee, T. W. Noh, and Jai‐Hyung Lee

Appl. Phys. Lett. 68, 472 (1996); http://dx.doi.org/10.1063/1.116417 (3 pages) | Cited 25 times

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Epitaxial LiNbO3 films with two orientations were grown on sapphire (1120) substrates using pulsed laser deposition. The film deposited at a low oxygen pressure (i.e., 10−4 Torr) was epitaxially grown along the a axis, and that at a oxygen pressure of 10−1 Torr was epitaxially grown along the c axis. Electro‐optic properties of these films were quite different, demonstrating importance of controlling the epitaxial growth behaviors. The birefringence measurements of the LiNbO3 (1120) film showed a quadratic electro‐optic behavior with an effective quadratic coefficient of 2.38×10−15 m2/V2. This behavior was analyzed in terms of the quadratic electro‐optic tensor for LiNbO3. © 1996 American Institute of Physics.
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78.20.Jq Electro-optical effects
81.15.Fg Pulsed laser ablation deposition

Experimental determination of the absorption strength of C–H vibrations for infrared analysis of hydrogenated carbon films

W. Jacob and M. Unger

Appl. Phys. Lett. 68, 475 (1996); http://dx.doi.org/10.1063/1.116418 (3 pages) | Cited 45 times

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Plasma‐deposited, hydrogenated carbon thin films were investigated by infrared analysis and high‐energy ion analysis. The absolute quantities of hydrogen in the films, as measured by ion beam analysis, and the strength of the C–H vibrational bands around 3000 cm−1 were compared to determine the average absorption strength for these bands. The absorption strength was found to vary by a factor of 4 depending on the structure of the hydrocarbon films. © 1996 American Institute of Physics.
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68.55.-a Thin film structure and morphology
78.35.+c Brillouin and Rayleigh scattering; other light scattering

Patterned self‐assembly of one‐dimensional arsenic particle arrays in GaAs by controlled precipitation

R. A. Kiehl, M. Yamaguchi, O. Ueda, N. Horiguchi, and N. Yokoyama

Appl. Phys. Lett. 68, 478 (1996); http://dx.doi.org/10.1063/1.116419 (3 pages) | Cited 12 times

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A process for the patterned self‐assembly of nanometer‐scale particles within a solid is described. The process uses crystal strain and composition to guide the formation of arsenic precipitates in GaAs‐based epitaxial layers grown at low temperature by molecular beam epitaxy. The lateral particle position is controlled by the strain produced by a surface stress structure while the vertical position is controlled by the epitaxial layer composition. Arsenic particles ∼16‐nm in diameter are fabricated in one‐dimensional arrays with a 23‐nm edge‐to‐edge particle spacing at a depth of 45 nm below stressors 200 nm in width, thereby demonstrating this technique. © 1996 American Institute of Physics.
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81.07.-b Nanoscale materials and structures: fabrication and characterization
81.16.-c Methods of micro- and nanofabrication and processing
85.35.-p Nanoelectronic devices

Domain inversion in LiTaO3 and LiNbO3 by electric field application on chemically patterned crystals

Cynthia Baron, Hsing Cheng, and Mool C. Gupta

Appl. Phys. Lett. 68, 481 (1996); http://dx.doi.org/10.1063/1.116420 (3 pages) | Cited 28 times

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We report a process for the formation of inverted ferroelectric domain regions in LiTaO3 and LiNbO3. This process involves the chemical patterning of the material surface by diffusion of Ti or ion exchange followed by domain inversion by a uniform electric field. The resultant periodic domain structure is applicable to first order quasi‐phase‐matched second‐harmonic generation (QPMSHG). In first order periodically poled crystals of Z‐cut LiTaO3, initial results have shown bulk conversion efficiencies of up to 2%/(W cm). A second‐harmonic conversion of 3 mW of blue wavelength power was observed from waveguide devices made on these crystals. © 1996 American Institute of Physics.
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42.65.Ky Frequency conversion; harmonic generation, including higher-order harmonic generation
77.80.Dj Domain structure; hysteresis
77.84.Ek Niobates and tantalates
77.84.Cg PZT ceramics and other titanates

Imprint of (Pb,La)(Zr,Ti)O3 thin films with various crystalline qualities

J. Lee and R. Ramesh

Appl. Phys. Lett. 68, 484 (1996); http://dx.doi.org/10.1063/1.116421 (3 pages) | Cited 52 times

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(Pb,La)(Zr,Ti)O3 (PLZT) thin films with various crystalline qualities, i.e., epitaxial, oriented, and polycrystalline, have been grow. These PLZT thin films cooled at various oxygen cooling pressures were found to have different asymmetric switching and imprint behaviors, depending on the crystalline quality of the PLZT thin films. It was found that the initial polarization state of as‐grown PLZT thin films is an important indicator to determine further imprint behavior. Epitaxial PLZT thin‐film capacitors were prepolarized in an as‐grown state and further exhibited the large dependence of asymmetric switching and imprint behavior on the oxygen cooling pressure. On the other hand, oriented or polycrystalline PLZT capacitors exhibited very weak polarization and little dependence of the initial prepolarization state on the oxygen cooling pressure. Consequently, the PLZT capacitors containing polycrystalline nature had a strong resistance to the imprint failure. © 1996 American Institute of Physics.
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77.80.-e Ferroelectricity and antiferroelectricity
77.84.Ek Niobates and tantalates
77.84.Cg PZT ceramics and other titanates
85.50.-n Dielectric, ferroelectric, and piezoelectric devices

Effect of nitrogen–oxygen complex on electrical properties of Czochralski silicon

Deren Yang, Ruixing Fan, Liben Li, Duanlin Que, and Koji Sumino

Appl. Phys. Lett. 68, 487 (1996); http://dx.doi.org/10.1063/1.116422 (3 pages) | Cited 33 times

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Effect of nitrogen–oxygen (N–O) complexes on electrical properties of nitrogen‐rich Czochralski (CZ) silicon grown in a nitrogen atmosphere has been investigated during annealing in the temperature range from 650 to 1000 °C. Electrical and low temperature (8 K) Fourier transmission infrared spectrometer (FTIR) measurements point out that the carrier concentration of the nitrogen‐rich silicon varies with the annealing time and temperature, which is due to the formation and elimination of the N–O complexes acting as shallow thermal donors. After the N–O complexes are eliminated by annealing above 900 °C the carrier concentration of the nitrogen‐rich silicon is stabilized. It is suggested that the N–O complexes attract more oxygen atoms to form new electrically inactive N–O clusters, and lose their electrical activity. © 1996 American Institute of Physics.
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61.72.Cc Kinetics of defect formation and annealing
61.72.uf Ge and Si
71.55.Cn Elemental semiconductors

Growth‐related stress and surface morphology in homoepitaxial SrTiO3 films

E. J. Tarsa, E. A. Hachfeld, F. T. Quinlan, J. S. Speck, and M. Eddy

Appl. Phys. Lett. 68, 490 (1996); http://dx.doi.org/10.1063/1.116376 (3 pages) | Cited 67 times

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The lattice parameter and surface morphology of homoepitaxial SrTiO3 films were found to depend on the ambient oxygen pressure during growth. The homoepitaxial layers were grown by pulsed laser deposition with static ambient oxygen pressures of 100, 10, and 1 mTorr. The surface roughness of the films increased with increasing ambient growth pressure. In each case, the measured out‐of‐plane lattice parameter of the film was larger than that of the substrate. The mismatch between film and substrate increased with decreasing growth pressure. Compressive stresses of ∼0.28, 1.2, and 2.0 GPa were determined for homoepitaxial SrTiO3 layers deposited at 100, 10, and 1 mTorr, respectively. © 1996 American Institute of Physics.
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68.55.-a Thin film structure and morphology
81.15.Fg Pulsed laser ablation deposition

Formation of nanocrystals based on decomposition in the amorphous Zr41.2Ti13.8Cu12.5Ni10Be22.5 alloy

S. Schneider, P. Thiyagarajan, and W. L. Johnson

Appl. Phys. Lett. 68, 493 (1996); http://dx.doi.org/10.1063/1.116377 (3 pages) | Cited 152 times

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Primary crystallization and decomposition in the bulk amorphous alloy Zr41.2Ti13.8Cu12.5Ni10Be22.5 have been studied by small angle neutron scattering (SANS), transmission electron microscopy (TEM), and differential scanning calorimetry (DSC). SANS data of samples annealed isothermally at 623 K exhibit an interference peak centered at q=0.46 nm−1 after an incubation time of about 100 min. TEM and DSC investigations confirm that the respective periodic variation in the scattering length density is due to the formation of nanocrystals embedded in the amorphous matrix. These observations suggest that during the incubation time a chemical decomposition process occurs and the related periodic composition fluctuations give rise to the observed periodic arrangement of the nanocrystals. © 1996 American Institute of Physics.
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61.43.Fs Glasses
81.05.Kf Glasses (including metallic glasses)

Direct observation of competitive adsorption of NO, O, and N on Rh(111) surface by scanning tunneling microscopy

Hongwei Xu and K. Y. Simon Ng

Appl. Phys. Lett. 68, 496 (1996); http://dx.doi.org/10.1063/1.116378 (3 pages) | Cited 4 times

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NO absorption on Rh(111) surface has been studied by scanning tunnel microscopy. NO molecules were observed when coadsorbed with oxygen or nitrogen atoms. NO molecules were found to form ordered islands with (4×4) symmetry. Coadsorption of NO and oxygen or nitrogen atoms shows competitive behavior on Rh(111). © 1996 American Institute of Physics.
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68.03.Fg Evaporation and condensation of liquids
68.43.Mn Adsorption kinetics
68.43.-h Chemisorption/physisorption: adsorbates on surfaces

Effects of carbon implantation on generation lifetime in silicon

Ibrahim Ban, Mehmet C. Öztürk, Kim Christensen, and Dennis M. Maher

Appl. Phys. Lett. 68, 499 (1996); http://dx.doi.org/10.1063/1.116379 (3 pages) | Cited 9 times

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In this study, we present characterization of metal–oxide–silicon (MOS) capacitors fabricated on carbon (C12) implanted Si substrates. Carbon was implanted at an energy of 50 keV with doses ranging from 1×1012 cm−2 to 4.1×1015 cm−2. Metal–oxide silicon capacitors were fabricated and used to determine the MOS capacitance–voltage (C–V) and capacitance–time (C–t) behavior. These measurements revealed a strong correlation between carrier lifetime and the C dose. Degradation in lifetime was observed for C dose levels as low as 4×1012 cm−2. At C doses equal to and above 6.4×1013 cm−2, extremely low generation lifetimes were obtained (∼10−7 s). On the other hand, for C dose levels higher than 2.7×1014 cm−2, a low accumulation capacitance was observed at high frequencies and attributed to hole traps. Below this dose, both flatband voltage and interface trap density of the C implanted samples were comparable to those of the monitors. © 1996 American Institute of Physics.
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61.80.Jh Ion radiation effects
73.40.Qv Metal-insulator-semiconductor structures (including semiconductor-to-insulator)
85.30.Tv Field effect devices

Scanning tunneling microscopy of undoped GaAs/AlGaAs heterostructures under laser irradiation

T. Takahashi, M. Yoshita, and H. Sakaki

Appl. Phys. Lett. 68, 502 (1996); http://dx.doi.org/10.1063/1.116380 (3 pages) | Cited 7 times

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Scanning tunneling microscopy (STM) of cleaved surfaces of undoped GaAs/AlGaAs heterostructures has been performed under laser irradiation, by which the tunneling current is strongly enhanced via photocarrier generation. Clear STM images are obtained with high contrast between the GaAs and the AlGaAs layers when the laser wavelength is 800 nm which creates photocarriers only in the GaAs regions. It is found that the STM tip height difference between the GaAs and the AlGaAs regions reaches as large as 25 nm in the constant‐current mode. © 1996 American Institute of Physics.
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68.37.Ef Scanning tunneling microscopy (including chemistry induced with STM)
68.37.Ps Atomic force microscopy (AFM)
68.37.Rt Magnetic force microscopy (MFM)
68.37.Uv Near-field scanning microscopy and spectroscopy

Molecular beam epitaxial growth of InSb, GaSb, and AlSb nanometer‐scale dots on GaAs

Brian R. Bennett, R. Magno, and B. V. Shanabrook

Appl. Phys. Lett. 68, 505 (1996); http://dx.doi.org/10.1063/1.116381 (3 pages) | Cited 56 times

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Thin layers of InSb, GaSb, and AlSb were grown on GaAs substrates by molecular beam epitaxy. Atomic force microscopy was used to examine surface morphology as a function of growth temperature and monolayer coverage. For each material, conditions were found which resulted in Stranski–Krastanov growth with the strain‐induced formation of nanometer‐scale dots. Relatively uniform distributions of dots form in a temperature window near the congruent sublimation temperature for both InSb and GaSb. In the case of InSb, deposition of 2 monolayers at 430 °C produced a surface with 3×109/cm2 dots with heights of 58±5 Å and diameters of 600±50 Å.
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81.15.Hi Molecular, atomic, ion, and chemical beam epitaxy
81.07.-b Nanoscale materials and structures: fabrication and characterization
81.16.-c Methods of micro- and nanofabrication and processing
85.35.-p Nanoelectronic devices
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